Question: Ben starts counting at 43, and he counts by fours. If 43 is the 1st number that Ben counts. what is the 11th number that he counts?
Solution: What is the first number that he counts? $43$ What is the second number that he counts? $\begin{align*}&43 + 4 \\ &= 47\end{align*}$ What is the third number that he counts? $\begin{align*}&43 + 4 + 4 \\ &= 43 + (2 \times 4) \\ &= 51\end{align*}$ What is the 11th number that he counts? $\begin{align*}&43 + (10\times4) \\ &= 43 + 40 \\ &= 83\end{align*}$